INTRODUCTION
In my opinion, the E90 M3 is pretty fast, but I found the power delivery of the car to be somewhat bland and mundane. When compared to my near full bolt-on and tuned E46 M3, I found the E90 M3 to be a tad weaker in the low-mid range of the powerband. On top of that, it didn't have much of a growl and snarl that a V8 should have.

One of the most popular power modifications for the E9X M3 is some sort of primary cat delete. The E9X M3 X-Pipe is equipped with both primary cats (immediately after the header) and secondary cats (further downstream before the crossover). Obviously the primary cats are rather restrictive considering that it creates an incredible amount of back pressure immediately after the collector of the stunning S65B40 headers. This primary cat delete is analogous to the catless headers that many E46 M3 owners upgrade to.

Considering some of my complaints of the car, I knew that some sort of primary cat delete was something I needed. I contemplated test pipes, eBay X-Pipes, and a slew of big brand name X-Pipes. Ultimately, I decided to get one of the top tier stainless steel X-Pipes. In the end, I acquired a stunning X-Pipe designed by Evolve Automotive. What I really like about their X-Pipe is that it had high flow catalytic converters and a pair of resonators. This means very high flow, low back pressure, low rasp, and low volume when paired with my stock muffler.

PERSONAL REVIEW
Sound - Cold start sounds insane, loud, and wicked! Warm idle is much more subtle, but there is a slight growl and rumble. Light throttle exhibits no drone, low volume, low rasp, yet a clean growling tone. Overall, very classy and tasteful. Heavy throttle provides a very noticeable roar! It sounds like the V8 is now very awake. Rasp is still very absent, but pure ferocity is heard on a quieter scale considering the stock muffler.

Smell - I honestly do not notice any difference. This was a huge relief considering my experience with my E46 M3 when I went catless. Cold start, warm idle, cruising, windows up, windows down, literally little to none presence of olfactory nuisance.

Fitment - 100% perfection.

Power - Incredibly noticeable. Completely rid of all my complaints. Very strong low-mid-high end power. Upon my first 50 miles of driving, I felt that there was just more power everywhere! I honestly was not expecting to feel that much of a difference considering the weight of the car, but it is absolutely profound. At any point in the power band, you can mash the throttle and urgency will be present. I am only totally pleased and impressed by this very simple bolt-on modification. I wasn't sure what to expect when I finally got the chance to dyno. Upon analyzing the data, there is a very consistent 20-25whp gain all across the board! No wonder I felt such a big improvement in power regardless of state of the powerband.

DYNOS
2009 BMW E90 M3 DCT
DynoJet248X at Dean's Performance, St. Charles, IL
4th Gear | 220E | 93 Octane
Evolve Automotive X-Pipe w/ 200cpsi Cats
Evolve Automotive DCT SoftwareNotes: Consistent and realistic measurement was absolutely key with our data collection. To assure a proper controlled and accurate measurement, we assured to log several parameters to provide a level playing field. IATs were properly controlled and monitored for consistency. Ignition was logged so that the proper runs can be chosen where this does not become a variable, but a constant control. Please note how the ignition logs are identical between Stock and Evolve X-Pipe runs. To some degree, this strengthens the evidence of the sole effect of the X-Pipe and decreased back pressure. No dyno tricks, no misleading data, only candid and fair comparison. Notice how even the AFRs are nearly identical. Both of these logs prove that there is no tweaking of the DME, the MSS60 DME has stabilized for consistency, and most comparable runs were chosen.

20+ rwhp gain is great, particularly with 100 cell cats, and the gains start right at the beginning of your dyno run. Let us know if the 100 cell cats are sufficient to keep the CEL off. Akra needed its DeleteR with 100 cell cats.

Looks like Evolve puts the X was back like stock (where the stock bracket is) and uses curved pipe kissing together for the X like most of the other aftermarket x-pipes. I know there has been some debate about the benefit of locating it further forward, the angles of the pipes going in and out of the X, and whether the center of the X should be a kiss or whether one pipe should actually cross through the other pipe.

Yup! Will be getting an Evolve Automotive Stage 2 Tune very soon, followed by more dyno runs.

Quote:

Originally Posted by robguenther13

I believe it said Evolve DCT tune on the Dyno sheet.

I have the Evolve DCT Software, but not their Stage 2 MSS60 Tune.

Quote:

Originally Posted by MisterEm

Nice Alex. Next time we come to Chicago - bring out the E90!

YESSIR!!! The X-Pipe really wakes up the car. I can't wait for the next hang out

Quote:

Originally Posted by pbonsalb

20+ rwhp gain is great, particularly with 100 cell cats, and the gains start right at the beginning of your dyno run. Let us know if the 100 cell cats are sufficient to keep the CEL off. Akra needed its DeleteR with 100 cell cats.

Looks like Evolve puts the X was back like stock (where the stock bracket is) and uses curved pipe kissing together for the X like most of the other aftermarket x-pipes. I know there has been some debate about the benefit of locating it further forward, the angles of the pipes going in and out of the X, and whether the center of the X should be a kiss or whether one pipe should actually cross through the other pipe.

I got a CEL in about 25miles of driving for Post-Cat O2 insufficiency.

Yeah I am still waiting to see proper data collection comparing the different designs of X-Pipes out there. Seeing proper logging of ignition, IATs, AFRs, etc to reduce any confounding variables would be truly beneficial, rather than just speculation.

Quote:

Originally Posted by DLSJ5

Good stuff Alex, what's next?

Thanks Drew! What's next? Living vicariously through you and IMG and your insane power.

What really is next though, just an Evolve Automotive Stage 2 tune...then I'm getting some BOOOOOOOOOOOST... for the E46 M3

20+ rwhp gain is great, particularly with 100 cell cats, and the gains start right at the beginning of your dyno run. Let us know if the 100 cell cats are sufficient to keep the CEL off. Akra needed its DeleteR with 100 cell cats..

Well both x pipes have cats located after the primary and secondary o2 sensors, so they have zero impact on passing emissions.

There are no cats on either pipe between the primary and secondary o2s, so clearly the car will throw cel

Excellent gains my man! Car must feel a ton faster with the huge torque delta across the entire range!

Thanks buddy! It's not supercharger fast, but it sure is very substantial on the road. So far I'm loving it!

Quote:

Originally Posted by ILSMKU

Dct tune is transmission. No?

You are correct. I solely have the DCT Software, nothing for the engine.

Quote:

Originally Posted by KennyPowers

Well both x pipes have cats located after the primary and secondary o2 sensors, so they have zero impact on passing emissions.

There are no cats on either pipe between the primary and secondary o2s, so clearly the car will throw cel

You are correct, I threw code almost instantly.

Quote:

Originally Posted by pkim1079

great gains! but that looks like a home made job.....I hope it wasn't pricey!

Thanks! I actually bought this X-Pipe used, I might even be the third owner. This specific X-Pipe was a pre-production piece, so the welding might not have been grinded down to look pretty. Trust me though, this is far from home made.

I have seen brand new production Evolve Automotive X-Pipes and the welding certainly does look prettier, but function wise, I imagine them to be exactly the same. For reference, here's a studio photo of a brand new X-Pipe.

Since I bought mine used, I'm not sure if Evolve Automotive gives out M3Post discounts. I think it's well worth contacting them about.

Weight: I did not weigh it, which I regret now. I wish I had.
Inner Diameter: 2.5" like most popular options. Difference between this and stock is that it's a full circle throughout. No crush bends, no crimping, no pancaking of the piping. For what it's worth, Evolve Automotive did announce that they will be R&Ding larger piping in the future.

Since I bought mine used, I'm not sure if Evolve Automotive gives out M3Post discounts. I think it's well worth contacting them about.

Weight: I did not weigh it, which I regret now. I wish I had.
Inner Diameter: 2.5" like most popular options. Difference between this and stock is that it's a full circle throughout. No crush bends, no crimping, no pancaking of the piping. For what it's worth, Evolve Automotive did announce that they will be R&Ding larger piping in the future.